Scheduling of transmission time intervals

ABSTRACT

Apparatuses, methods, and systems are disclosed for scheduling of transmission time intervals. One apparatus includes a processor that determines a first semi-persistent scheduling resource assignment indicating a first set of resources including a first multiple time domain resources. Each time domain resource of the first multiple time domain resources has a first transmission time interval length. The processor also determines a second semi-persistent scheduling resource assignment indicating a second set of resources including a second multiple time domain resources. Each time domain resource of the second multiple time domain resources has a second transmission time interval length, and the first transmission time interval length is different from the second transmission time interval length. The apparatus includes a transmitter that transmits the first semi-persistent scheduling resource assignment using a first semi-persistent scheduling radio network identifier, and transmits the second semi-persistent scheduling resource assignment using a second semi-persistent scheduling radio network identifier.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application of and claims priorityto U.S. Patent Application Ser. No. 62/321,657 entitled “SCHEDULING OFTRANSMISSION TIME INTERVALS” and filed on Apr. 12, 2016 for HosseinBagheri et al., which is incorporated herein by reference in itsentirety.

FIELD

The subject matter disclosed herein relates generally to wirelesscommunications and more particularly relates to scheduling oftransmission time intervals (“TTIs”) in a wireless communication system.

BACKGROUND

In wireless communications networks, a frame structure for long termevolution (“LTE”) frequency division duplex (“FDD”) may be used.Alternatively, a frame structure for time division duplex (“FDD”) may beused. A radio frame of 10 milliseconds (“ms”) may include 10 subframes,each of which is 1 ms. Each subframe further may include two slots, eachof which is 0.5 ms. Within each slot, a number of orthogonalfrequency-division multiplexing (“OFDM”) symbols may be transmitted. Thetransmitted signal in each slot on an antenna port may be described by aresource grid comprising N_(RB) ^(DL)N_(sc) ^(RB) subcarriers andN_(symb) ^(DL) OFDM symbols, where N_(RB) ^(DL) is a number of resourceblocks (“RBs”) in the downlink (“DL”) (which is dependent on thetransmission bandwidth of a cell); N_(sc) ^(RB) is the number ofsubcarriers in each RB; and each subcarrier occupies a certain frequencyof size Δf. The values of N_(sc) ^(RB), Δf, and N_(symb) ^(DL) maydepend on a cyclic prefix as shown in Table 1.

TABLE 1 Configuration N_(sc) ^(RB) N_(symb) ^(DL) Normal Cyclic PrefixΔf = 15 kHz 12 7 Extended Cyclic Prefix Δf = 15 kHz 6 Δf = 7.5 kHz 24 3

In certain configurations, an antenna port may refer to a logicalantenna port (i.e., it may not necessarily refer to a physical antennaor antenna element). Mapping between an antenna port and physicalantenna element(s) may be implementation specific. In other words,different devices may have a different mapping of physical antennaelement(s) to the same antenna port. A receiving device may assume thatthe signals transmitted on the same antenna port go through the samechannel. Moreover, a receiving device cannot assume signals transmittedon different antenna ports go through the same channel.

In certain wireless communication networks, the transmission timeinterval (“TTI”) may be 1 ms. In other wireless communication networks,such as networks using shortened TTIs (“s-TTIs”), the s-TTI may be lessthan 1 ms. In such wireless communication networks, semi-persistentscheduling (“SPS”) may be used. In some wireless communication networks,scheduling conflicts may occur.

BRIEF SUMMARY

Apparatuses for scheduling of transmission time intervals are disclosed.Methods and systems also perform the functions of the apparatus. In oneembodiment, an apparatus includes a processor that determines a firstsemi-persistent scheduling resource assignment indicating a first set ofresources, the first set of resources including a first multiple timedomain resources. In such an embodiment, each time domain resource ofthe first multiple time domain resources has a first transmission timeinterval length. The processor also determines a second semi-persistentscheduling resource assignment indicating a second set of resources, thesecond set of resources including a second multiple time domainresources. In such embodiments, each time domain resource of the secondmultiple time domain resources has a second transmission time intervallength, and the first transmission time interval length is differentfrom the second transmission time interval length. In certainembodiments, the apparatus includes a transmitter that transmits thefirst semi-persistent scheduling resource assignment using a firstsemi-persistent scheduling radio network identifier, and transmits thesecond semi-persistent scheduling resource assignment using a secondsemi-persistent scheduling radio network identifier.

In certain embodiments, a method includes determining a firstsemi-persistent scheduling resource assignment indicating a first set ofresources, the first set of resources including a first multiple timedomain resources. In such embodiments, each time domain resource of thefirst multiple time domain resources has a first transmission timeinterval length. The method also includes determining a secondsemi-persistent scheduling resource assignment indicating a second setof resources, the second set of resources including a second multipletime domain resources. In such embodiments, each time domain resource ofthe second multiple time domain resources has a second transmission timeinterval length, and the first transmission time interval length isdifferent from the second transmission time interval length. The methodincludes transmitting the first semi-persistent scheduling resourceassignment using a first semi-persistent scheduling radio networkidentifier. The method also includes transmitting the secondsemi-persistent scheduling resource assignment using a secondsemi-persistent scheduling radio network identifier.

In certain embodiments, the first semi-persistent scheduling radionetwork identifier and the second semi-persistent scheduling radionetwork identifier are the same. In some embodiments, the firstsemi-persistent scheduling radio network identifier and the secondsemi-persistent scheduling radio network identifier are different. Invarious embodiments, the first and second semi-persistent schedulingresource assignments are for uplink transmissions. In one embodiment,the first and second semi-persistent scheduling resource assignments arefor downlink transmissions. In certain embodiments, the method includesdetermining a location of the first semi-persistent scheduling resourceassignment based on a first number of symbols and determining a locationof the second semi-persistent scheduling resource assignment based on asecond number of symbols. In some embodiments, the method includestransmitting information indicating a location in a subframe for one ormore of semi-persistent scheduling activation and semi-persistentscheduling deactivation commands. In various embodiments, the methodincludes transmitting information indicating one or more ofsemi-persistent scheduling activation and semi-persistent schedulingdeactivation commands in a predetermined location in a subframe.

Another apparatus includes a receiver that receives a firstsemi-persistent scheduling resource assignment indicating a first set ofresources, the first set of resources including a first multiple timedomain resources. In such embodiments, each time domain resource of thefirst multiple time domain resources has a first transmission timeinterval length. The receiver also receives a second semi-persistentscheduling resource assignment indicating a second set of resources, thesecond set of resources including a second multiple time domainresources. In such embodiments, each time domain resource of the secondmultiple time domain resources has a second transmission time intervallength, and the first transmission time interval length is differentfrom the second transmission time interval length. The apparatusincludes a processor that determines the first semi-persistentscheduling resource assignment using a first semi-persistent schedulingradio network identifier, and determines the second semi-persistentscheduling resource assignment using a second semi-persistent schedulingradio network identifier.

Another method includes receiving a first semi-persistent schedulingresource assignment indicating a first set of resources, the first setof resources including a first multiple time domain resources. In suchembodiments, each time domain resource of the first multiple time domainresources has a first transmission time interval length. The methodincludes receiving a second semi-persistent scheduling resourceassignment indicating a second set of resources, the second set ofresources including a second multiple time domain resources. In suchembodiments, each time domain resource of the second multiple timedomain resources has a second transmission time interval length, and thefirst transmission time interval length is different from the secondtransmission time interval length. The method also includes determiningthe first resource assignment using a first semi-persistent schedulingradio network identifier. The method includes determining the secondresource assignment using a second semi-persistent scheduling radionetwork identifier.

In one embodiment, the first semi-persistent scheduling resourceassignment is for uplink transmissions, and the method further includesreceiving a deactivation command, determining at least one time domainresource of the first multiple time domain resources, and, in responseto receiving the deactivation command, deactivating semi-persistentscheduling related data transmission on the at least one time domainresource of the first multiple time domain resources.

In some embodiments, the deactivation command is a first deactivationcommand, and the method further includes receiving a second deactivationcommand, and, in response to receiving the second deactivation command,deactivating semi-persistent scheduling related data transmission untilreception of a semi-persistent scheduling activation command or asemi-persistent scheduling reactivation command. In various embodiments,the first transmission time interval length corresponds to a firstnumber of symbols, and the second transmission time interval lengthcorresponds to a second number of symbols.

A further method includes receiving a first semi-persistent schedulingresource assignment indicating a first set of periodic time domainresources. In such embodiments, each resource of the first set ofperiodic time domain resources has a first transmission time intervallength. The method also includes determining a first resource of thefirst set of periodic time domain resources that overlaps with aresource used for transmissions based on a second transmission timeinterval length. The method includes determining a second resource ofthe first transmission time interval length that does not overlap withthe resource used for transmissions based on the second transmissiontime interval length. The method also includes using the second resourcefor semi-persistent scheduling related data transmissions and not usingthe first resource for semi-persistent scheduling related datatransmissions. In such embodiments, the first transmission time intervallength and the second transmission time interval length are different.

In one embodiment, the method includes receiving a message indicatingthe resources used for transmissions based on the second transmissiontime interval length. In some embodiments, the first transmission timeinterval length corresponds to a shortened transmission time intervallength, and the second transmission time interval length corresponds toa legacy transmission time interval length, and the shortenedtransmission time interval length is smaller than the legacytransmission time interval length. In various embodiments, the methodincludes determining the second resource from the first set of periodictime domain resources.

In certain embodiments, the method includes determining the secondresource from a third set of time domain resources not overlapping withthe first set of periodic time domain resources. In one embodiment, themethod includes determining the second resource based on time domaininformation of the first resource and the time domain information of theresource used for transmissions based on the second transmission timeinterval length. In some embodiments, the first semi-persistentscheduling resource assignment includes a bit-map pattern. In variousembodiments, a periodicity of the first set of time domain resources isdefined based on a number of transmission time intervals. In certainembodiments, the method includes receiving an indication that indicatesa third transmission time interval length for the first semi-persistentscheduling resource assignment, and determining the periodicity of thefirst time domain resources based on the third transmission timeinterval length. In such embodiments, the first transmission timeinterval length and the third transmission time interval length aredifferent.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the embodiments briefly described abovewill be rendered by reference to specific embodiments that areillustrated in the appended drawings. Understanding that these drawingsdepict only some embodiments and are not therefore to be considered tobe limiting of scope, the embodiments will be described and explainedwith additional specificity and detail through the use of theaccompanying drawings, in which:

FIG. 1 is a schematic block diagram illustrating one embodiment of awireless communication system for scheduling of transmission timeintervals (“TTIs”);

FIG. 2 is a schematic block diagram illustrating one embodiment of anapparatus that may be used for scheduling of TTIs;

FIG. 3 is a schematic block diagram illustrating one embodiment of anapparatus that may be used for scheduling of TTIs;

FIG. 4 illustrates one embodiment of s-TTIs;

FIG. 5 illustrates another embodiment of s-TTIs;

FIG. 6 illustrates one embodiment of TTI scheduling;

FIG. 7 illustrates another embodiment of TTI scheduling;

FIG. 8 illustrates a further embodiment of TTI scheduling;

FIG. 9 illustrates yet another embodiment of TTI scheduling;

FIG. 10 is a schematic flow chart diagram illustrating one embodiment ofa method for scheduling of TTIs; and

FIG. 11 is a schematic flow chart diagram illustrating anotherembodiment of a method for scheduling of TTIs.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art, aspects of theembodiments may be embodied as a system, apparatus, method, or programproduct. Accordingly, embodiments may take the form of an entirelyhardware embodiment, an entirely software embodiment (includingfirmware, resident software, micro-code, etc.) or an embodimentcombining software and hardware aspects that may all generally bereferred to herein as a “circuit,” “module” or “system.” Furthermore,embodiments may take the form of a program product embodied in one ormore computer readable storage devices storing machine readable code,computer readable code, and/or program code, referred hereafter as code.The storage devices may be tangible, non-transitory, and/ornon-transmission. The storage devices may not embody signals. In acertain embodiment, the storage devices only employ signals foraccessing code.

Certain of the functional units described in this specification may belabeled as modules, in order to more particularly emphasize theirimplementation independence. For example, a module may be implemented asa hardware circuit comprising custom very-large-scale integration(“VLSI”) circuits or gate arrays, off-the-shelf semiconductors such aslogic chips, transistors, or other discrete components. A module mayalso be implemented in programmable hardware devices such as fieldprogrammable gate arrays, programmable array logic, programmable logicdevices or the like.

Modules may also be implemented in code and/or software for execution byvarious types of processors. An identified module of code may, forinstance, include one or more physical or logical blocks of executablecode which may, for instance, be organized as an object, procedure, orfunction. Nevertheless, the executables of an identified module need notbe physically located together, but may include disparate instructionsstored in different locations which, when joined logically together,include the module and achieve the stated purpose for the module.

Indeed, a module of code may be a single instruction, or manyinstructions, and may even be distributed over several different codesegments, among different programs, and across several memory devices.Similarly, operational data may be identified and illustrated hereinwithin modules, and may be embodied in any suitable form and organizedwithin any suitable type of data structure. The operational data may becollected as a single data set, or may be distributed over differentlocations including over different computer readable storage devices.Where a module or portions of a module are implemented in software, thesoftware portions are stored on one or more computer readable storagedevices.

Any combination of one or more computer readable medium may be utilized.The computer readable medium may be a computer readable storage medium.The computer readable storage medium may be a storage device storing thecode. The storage device may be, for example, but not limited to, anelectronic, magnetic, optical, electromagnetic, infrared, holographic,micromechanical, or semiconductor system, apparatus, or device, or anysuitable combination of the foregoing.

More specific examples (a non-exhaustive list) of the storage devicewould include the following: an electrical connection having one or morewires, a portable computer diskette, a hard disk, a random access memory(“RAM”), a read-only memory (“ROM”), an erasable programmable read-onlymemory (“EPROM” or Flash memory), a portable compact disc read-onlymemory (“CD-ROM”), an optical storage device, a magnetic storage device,or any suitable combination of the foregoing. In the context of thisdocument, a computer readable storage medium may be any tangible mediumthat can contain, or store a program for use by or in connection with aninstruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may be any number oflines and may be written in any combination of one or more programminglanguages including an object oriented programming language such asPython, Ruby, Java, Smalltalk, C++, or the like, and conventionalprocedural programming languages, such as the “C” programming language,or the like, and/or machine languages such as assembly languages. Thecode may execute entirely on the user's computer, partly on the user'scomputer, as a stand-alone software package, partly on the user'scomputer and partly on a remote computer or entirely on the remotecomputer or server. In the latter scenario, the remote computer may beconnected to the user's computer through any type of network, includinga local area network (“LAN”) or a wide area network (“WAN”), or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider).

Reference throughout this specification to “one embodiment,” “anembodiment,” or similar language means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment. Thus, appearances of the phrases“in one embodiment,” “in an embodiment,” and similar language throughoutthis specification may, but do not necessarily, all refer to the sameembodiment, but mean “one or more but not all embodiments” unlessexpressly specified otherwise. The terms “including,” “comprising,”“having,” and variations thereof mean “including but not limited to,”unless expressly specified otherwise. An enumerated listing of itemsdoes not imply that any or all of the items are mutually exclusive,unless expressly specified otherwise. The terms “a,” “an,” and “the”also refer to “one or more” unless expressly specified otherwise.

Furthermore, the described features, structures, or characteristics ofthe embodiments may be combined in any suitable manner. In the followingdescription, numerous specific details are provided, such as examples ofprogramming, software modules, user selections, network transactions,database queries, database structures, hardware modules, hardwarecircuits, hardware chips, etc., to provide a thorough understanding ofembodiments. One skilled in the relevant art will recognize, however,that embodiments may be practiced without one or more of the specificdetails, or with other methods, components, materials, and so forth. Inother instances, well-known structures, materials, or operations are notshown or described in detail to avoid obscuring aspects of anembodiment.

Aspects of the embodiments are described below with reference toschematic flowchart diagrams and/or schematic block diagrams of methods,apparatuses, systems, and program products according to embodiments. Itwill be understood that each block of the schematic flowchart diagramsand/or schematic block diagrams, and combinations of blocks in theschematic flowchart diagrams and/or schematic block diagrams, can beimplemented by code. These code may be provided to a processor of ageneral purpose computer, special purpose computer, or otherprogrammable data processing apparatus to produce a machine, such thatthe instructions, which execute via the processor of the computer orother programmable data processing apparatus, create means forimplementing the functions/acts specified in the schematic flowchartdiagrams and/or schematic block diagrams block or blocks.

The code may also be stored in a storage device that can direct acomputer, other programmable data processing apparatus, or other devicesto function in a particular manner, such that the instructions stored inthe storage device produce an article of manufacture includinginstructions which implement the function/act specified in the schematicflowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable dataprocessing apparatus, or other devices to cause a series of operationalsteps to be performed on the computer, other programmable apparatus orother devices to produce a computer implemented process such that thecode which execute on the computer or other programmable apparatusprovide processes for implementing the functions/acts specified in theflowchart and/or block diagram block or blocks.

The schematic flowchart diagrams and/or schematic block diagrams in theFigures illustrate the architecture, functionality, and operation ofpossible implementations of apparatuses, systems, methods and programproducts according to various embodiments. In this regard, each block inthe schematic flowchart diagrams and/or schematic block diagrams mayrepresent a module, segment, or portion of code, which includes one ormore executable instructions of the code for implementing the specifiedlogical function(s).

It should also be noted that, in some alternative implementations, thefunctions noted in the block may occur out of the order noted in theFigures. For example, two blocks shown in succession may, in fact, beexecuted substantially concurrently, or the blocks may sometimes beexecuted in the reverse order, depending upon the functionalityinvolved. Other steps and methods may be conceived that are equivalentin function, logic, or effect to one or more blocks, or portionsthereof, of the illustrated Figures.

Although various arrow types and line types may be employed in theflowchart and/or block diagrams, they are understood not to limit thescope of the corresponding embodiments. Indeed, some arrows or otherconnectors may be used to indicate only the logical flow of the depictedembodiment. For instance, an arrow may indicate a waiting or monitoringperiod of unspecified duration between enumerated steps of the depictedembodiment. It will also be noted that each block of the block diagramsand/or flowchart diagrams, and combinations of blocks in the blockdiagrams and/or flowchart diagrams, can be implemented by specialpurpose hardware-based systems that perform the specified functions oracts, or combinations of special purpose hardware and code.

The description of elements in each figure may refer to elements ofproceeding figures. Like numbers refer to like elements in all figures,including alternate embodiments of like elements.

FIG. 1 depicts an embodiment of a wireless communication system 100 forscheduling of transmission time intervals (“TTIs”). In one embodiment,the wireless communication system 100 includes remote units 102 and baseunits 104. Even though a specific number of remote units 102 and baseunits 104 are depicted in FIG. 1, one of skill in the art will recognizethat any number of remote units 102 and base units 104 may be includedin the wireless communication system 100.

In one embodiment, the remote units 102 may include computing devices,such as desktop computers, laptop computers, personal digital assistants(“PDAs”), tablet computers, smart phones, smart televisions (e.g.,televisions connected to the Internet), set-top boxes, game consoles,security systems (including security cameras), vehicle on-boardcomputers, network devices (e.g., routers, switches, modems), lowthroughput devices, low delay sensitivity devices, ultra-low costdevices, low power consumption devices, an IoT device, or the like. Insome embodiments, the remote units 102 include wearable devices, such assmart watches, fitness bands, optical head-mounted displays, or thelike. Moreover, the remote units 102 may be referred to as subscriberunits, mobiles, mobile stations, users, terminals, mobile terminals,fixed terminals, subscriber stations, user equipment (“UE”), userterminals, a device, or by other terminology used in the art. The remoteunits 102 may communicate directly with one or more of the base units104 via UL communication signals.

The base units 104 may be distributed over a geographic region. Incertain embodiments, a base unit 104 may also be referred to as anaccess point, an access terminal, a base, a base station, a Node-B, anevolved node B (“eNB”), a Home Node-B, a relay node, a device, or by anyother terminology used in the art. The base units 104 are generally partof a radio access network that may include one or more controllerscommunicably coupled to one or more corresponding base units 104. Theradio access network is generally communicably coupled to one or morecore networks, which may be coupled to other networks, like the Internetand public switched telephone networks, among other networks. These andother elements of radio access and core networks are not illustrated butare well known generally by those having ordinary skill in the art. Forexample, one or more base units 104 may be communicably coupled to amobility management entity (“MME”), a serving gateway (“SGW”), and/or apacket data network (“PDN”) gateway (“PGW”).

In one implementation, the wireless communication system 100 iscompliant with the LTE of the 3GPP protocol, wherein the base unit 104transmits using an OFDM modulation scheme on the DL and the remote units102 transmit on the uplink (“UL”) using a single carrierfrequency-division multiple access (“SC-FDMA”) scheme. In anotherimplementation, the wireless communication system 100 is compliant withnarrowband internet-of-things (“NB-IoT”). More generally, however, thewireless communication system 100 may implement some other open orproprietary communication protocol, for example, WiMAX, among otherprotocols. The present disclosure is not intended to be limited to theimplementation of any particular wireless communication systemarchitecture or protocol.

The base units 104 may serve a number of remote units 102 within aserving area, for example, a cell or a cell sector via a wirelesscommunication link. The base units 104 transmit DL communication signalsto serve the remote units 102 in the time, frequency, and/or spatialdomain.

In one embodiment, an apparatus (e.g., base unit 104) may determine afirst semi-persistent scheduling (“SPS”) radio network identifier(“RNI”) for a first resource assignment associated with a firsttransmission time interval (“TTI”) including a first number of symbols.RNI can include network temporary identifier (“RNTI”). The apparatus mayalso determine a second SPS RNI for a second resource assignmentassociated with a second TTI including a second number of symbolsdifferent from the first number of symbols. The apparatus may transmitinformation indicating the first resource assignment using the first SPSRNI, and information indicating the second resource assignment using thesecond SPS RNI. Therefore, SPS may be assigned for multiple TTIs ofdifferent size.

In a further embodiment, an apparatus (e.g., remote unit 102) mayreceive information indicating a first resource assignment associatedwith a first TTI including a first number of symbols. The apparatus mayalso receive information indicating a second resource assignmentassociated with a second TTI comprising a second number of symbolsdifferent from the first number of symbols. The apparatus may determinethe first resource assignment using a first SPS RNI. The apparatus mayalso determine the second resource assignment using a second SPS RNI. Inanother embodiment, the apparatus may determine the association of theresource assignment with the TTI length based on a location of resourceassignment. For example, a resource assignment received in a firstlocation or region in a subframe may be associated with a first TTI, anda resource assignment received in a second location or region in asubframe may be associated with a second TTI. The first and secondlocation or region may be non-overlapping, and the first and secondresource assignment may use the same SPS RNI.

FIG. 2 depicts one embodiment of an apparatus 200 that may be used forscheduling of TTIs. The apparatus 200 includes one embodiment of theremote unit 102. Furthermore, the remote unit 102 may include aprocessor 202, a memory 204, an input device 206, a display 208, atransmitter 210, and a receiver 212. In some embodiments, the inputdevice 206 and the display 208 are combined into a single device, suchas a touchscreen. In certain embodiments, the remote unit 102 may notinclude any input device 206 and/or display 208. In various embodiments,the remote unit 102 may include one or more of the processor 202, thememory 204, the transmitter 210, and the receiver 212, and may notinclude the input device 206 and/or the display 208.

The processor 202, in one embodiment, may include any known controllercapable of executing computer-readable instructions and/or capable ofperforming logical operations. For example, the processor 202 may be amicrocontroller, a microprocessor, a central processing unit (“CPU”), agraphics processing unit (“GPU”), an auxiliary processing unit, a fieldprogrammable gate array (“FPGA”), or similar programmable controller. Insome embodiments, the processor 202 executes instructions stored in thememory 204 to perform the methods and routines described herein. Theprocessor 202 is communicatively coupled to the memory 204, the inputdevice 206, the display 208, the transmitter 210, and the receiver 212.In certain embodiments, the processor 202 may determine the firstresource assignment using a first SPS RNI, and determine the secondresource assignment using a second SPS RNI.

The memory 204, in one embodiment, is a computer readable storagemedium. In some embodiments, the memory 204 includes volatile computerstorage media. For example, the memory 204 may include a random accessmemory (“RAM”), including dynamic RAM (“DRAM”), synchronous dynamic RAM(“SDRAM”), and/or static RAM (“SRAM”). In some embodiments, the memory204 includes non-volatile computer storage media. For example, thememory 204 may include a hard disk drive, a flash memory, or any othersuitable non-volatile computer storage device. In some embodiments, thememory 204 includes both volatile and non-volatile computer storagemedia. In some embodiments, the memory 204 stores data relating to anindication to be provided to another device. In some embodiments, thememory 204 also stores program code and related data, such as anoperating system or other controller algorithms operating on the remoteunit 102.

The input device 206, in one embodiment, may include any known computerinput device including a touch panel, a button, a keyboard, a stylus, amicrophone, or the like. In some embodiments, the input device 206 maybe integrated with the display 208, for example, as a touchscreen orsimilar touch-sensitive display. In some embodiments, the input device206 includes a touchscreen such that text may be input using a virtualkeyboard displayed on the touchscreen and/or by handwriting on thetouchscreen. In some embodiments, the input device 206 includes two ormore different devices, such as a keyboard and a touch panel.

The display 208, in one embodiment, may include any known electronicallycontrollable display or display device. The display 208 may be designedto output visual, audible, and/or haptic signals. In some embodiments,the display 208 includes an electronic display capable of outputtingvisual data to a user. For example, the display 208 may include, but isnot limited to, a liquid crystal display (“LCD”), a light emitting diode(“LED”) display, an organic light emitting diode (“OLED”) display, aprojector, or similar display device capable of outputting images, text,or the like to a user. As another, non-limiting, example, the display208 may include a wearable display such as a smart watch, smart glasses,a heads-up display, or the like. Further, the display 208 may be acomponent of a smart phone, a personal digital assistant, a television,a table computer, a notebook (laptop) computer, a personal computer, avehicle dashboard, or the like.

In certain embodiments, the display 208 includes one or more speakersfor producing sound. For example, the display 208 may produce an audiblealert or notification (e.g., a beep or chime). In some embodiments, thedisplay 208 includes one or more haptic devices for producingvibrations, motion, or other haptic feedback. In some embodiments, allor portions of the display 208 may be integrated with the input device206. For example, the input device 206 and display 208 may form atouchscreen or similar touch-sensitive display. In other embodiments,the display 208 may be located near the input device 206.

The transmitter 210 is used to provide UL communication signals to thebase unit 104 and the receiver 212 is used to receive informationindicating a first resource assignment associated with a first TTIincluding a first number of symbols. In some embodiments, the receiver212 is used to receive information indicating a second resourceassignment associated with a second TTI comprising a second number ofsymbols different from the first number of symbols. In one embodiment,the transmitter 210 is used to transmit feedback information and/or anindication to the base unit 104. Although only one transmitter 210 andone receiver 212 are illustrated, the remote unit 102 may have anysuitable number of transmitters 210 and receivers 212. The transmitter210 and the receiver 212 may be any suitable type of transmitters andreceivers. In one embodiment, the transmitter 210 and the receiver 212may be part of a transceiver.

FIG. 3 depicts one embodiment of an apparatus 300 that may be used forscheduling of TTIs. The apparatus 300 includes one embodiment of thebase unit 104. Furthermore, the base unit 104 may include a processor302, a memory 304, an input device 306, a display 308, a transmitter310, and a receiver 312. It should be noted that the processor 302, thememory 304, the input device 306, and the display 308 may besubstantially similar to the processor 202, the memory 204, the inputdevice 206, and the display 208 of the remote unit 102, respectively. Incertain embodiments, the processor 302 may be used to determine a firstSPS RNI for a first resource assignment associated with a first TTIincluding a first number of symbols. In some embodiments, the processor302 may be used to determine a second SPS RNI for a second resourceassignment associated with a second TTI comprising a second number ofsymbols different from the first number of symbols.

The transmitter 310 is used to provide DL communication signals to theremote unit 102 and the receiver 312 is used to receive UL communicationsignals from the remote unit 102. In certain embodiments, thetransmitter 310 is used to transmit information indicating the firstresource assignment using the first SPS RNI, and to transmit informationindicating the second resource assignment using the second SPS RNI. Itshould be noted that, in certain embodiments, an MME, an SGW, and/or aPGW may include one or more components found in the base unit 104.Furthermore, in certain embodiments, the base unit 104 may represent oneembodiment of an MME, an SWG or a PGW.

FIG. 4 illustrates one embodiment of s-TTIs 400 using a normal cyclicprefix as an example. In the illustrated embodiment, each s-TTI is halfthe length of a standard size TTI of 1 ms. Accordingly, each s-TTI is0.5 ms. As illustrated, each s-TTI includes seven OFDM symbols 402. FIG.5 illustrates another embodiment of s-TTIs 500, again using a normalcyclic prefix as an example. In this embodiment, some s-TTIs includefour OFDM symbols 402, and some s-TTIs include three OFDM symbols 402.It should be noted that an s-TTI may include any number of OFDM symbols402 that is less than a standard size TTI. In this disclosure, a UE thatis configured to use s-TTI may be referred to as an s-UE (e.g., remoteunit 102), while a UE not configured to use s-TTI may be referred to asa legacy UE. In certain embodiments, the subcarrier spacing and thecyclic prefix length may be common to both legacy UEs and s-UEs.

In certain configurations, dynamic scheduling may be good for burstinginfrequent and bandwidth consuming data transmissions (e.g. web surfing,video streaming, emails). However, dynamic scheduling may be lesssuitable for real time streaming. Semi-persistent scheduling (“SPS”) isa transmission method that defines a transmission pattern instead ofscheduling a single uplink or downlink transmission. In certainembodiments, SPS may reduce scheduling assignment overhead, and mayenable data communication with lower latency as there is no need toobtain/generate scheduling assignment information for a singletransmission. SPS operation combined with s-TTI may reduce schedulingassignment overhead. It should be noted that remote unit 102transmissions may be either received by one or more base stations orother remote units 102 in a communication network.

In certain LTE systems, a base unit 104 may configure and/or reconfigurea remote unit 102 with SPS at any time by radio resource control (“RRC”)using an SPS configuration (“SPS-Config”). The SPS-Config may includethe configuration for an SPS cell radio network temporary identifier(“C-RNTI”) (“SPS-C-RNTI), SPS downlink configuration (“SPS-ConfigDL”),and/or SPS uplink configuration (“SPS-ConfigUL”). When configuring SPSin any direction either UL or DL, SPS C-RNTI may be provided by the baseunit 104. After a remote unit 102 is configured with SPS C-RNTI, theremote unit 102 may be configured by higher layers to decode physicaldownlink control channel (“PDCCH”) with cyclic redundancy code (“CRC”)scrambled by the SPS C-RNTI. A remote unit 102 may monitor PDCCH withCRC scrambled by the SPS C-RNTI in every subframe as the base unit 104may activate, reactivate, and/or release SPS at any time using downlinkcontrol information (“DCI”).

When s-TTI is enabled in a system, a remote unit 102 may be configuredto use different TTI lengths for different packet types (e.g., 1 ms TTImay be used for voice packets, 0.5 ms TTI length may be used for apacket with low-latency requirements, and 2 symbol TTI length may beused for a packet with super low-latency requirements). Therefore, aremote unit 102 may be configured with more than one SPS configuration,and each SPS configuration may have a different TTI length (e.g., an SPSconfiguration for voice using 1 ms TTI, another SPS configuration fors-TTI=2 symbols, and another SPS configuration for s-TTI=0.5 ms).

In certain embodiments, to enable multiple SPS configurations withdifferent TTI lengths, multiple approaches may be used for both UL andDL.

For example, in one embodiment, each SPS configuration for a remote unit102 corresponds to a different TTI length and has its own correspondingSPS-C-RNTI. The remote unit 102 may receive the SPS configurations viadedicated RRC signaling for each TTI length the remote unit 102 isconfigured to use. Each SPS configuration RRC signal contains its ownSPS-C-RNTI. The base unit 104 may scramble PDCCH (e.g., enhanced PDCCH(“EPDCCH”)) corresponding to the TTI length with CRC scrambled by theSPS-C-RNTI associated with the SPS configuration of that TTI length,such as in every s-TTI in which the control information is monitored.The remote unit 102 may monitor the PDCCH with CRC scrambled by theSPS-C-RNTI in every s-TTI in which the control information is monitored.

As another example, in certain embodiments, all SPS configurations forthe remote unit 102 may use the same SPS-C-RNTI. The remote unit 102 mayreceive the SPS configurations via dedicated RRC signaling for each TTIlength the remote unit 102 is configured to use. Each SPS configurationRRC signal contain the same SPS-C-RNTI. The base unit 104 may scramblesPDCCH corresponding to the TTI length with CRC scrambled by the sameSPS-C-RNTI in every s-TTI in which the control information is monitored.In certain embodiments, control information regarding the s-TTIoperation may be transmitted in 2 parts for SPS for s-TTI. In suchembodiments, one part or both parts may be scrambled with SPS-C-RNTI.For example, 2 part transmission may include transmissions foractivation, release, validation, and so forth. The remote unit 102 maymonitor the PDCCH with CRC scrambled by the SPS-C-RNTI in every s-TTI inwhich the control information is monitored.

In some embodiments, such as when all SPS configurations use the sameSPS-C-RNTI, the remote unit 102 may need to distinguish which controlcommands are for which SPS configuration. Certain control commands maybe sent for activation and/or release of SPS, or for changing afrequency resource allocation of the SPS. For example, if a remote unit102 is configured for two SPS operations: one with TTI length of 1 msand the other one with TTI length of 2 symbol, upon reception of a PDCCHscrambled with SPS-C-RNTI, the remote unit 102 may need to figure out ifthis PDCCH command is for SPS with TTI length of 1 ms or for SPS withTTI length of 2-symbols.

In one embodiment, the remote unit 102 may deduce which SPSconfiguration the control command is directed to by the location of thereceived control command. For example, if the TTI that the PDCCH commandis received in is OFDM symbol 4, the command may not be for the 1 msTTI, but may be for an s-TTI that starts with symbol 4. In someembodiments, a time-frequency position of the PDCCH commands may be usedto indicate which SPS configuration the control command is directed to.In such embodiments, the remote unit 102 may receive an indication ofsuch time-frequency positions that may be used. In some embodiments, theremote unit may determine the association of the SPS configuration withthe TTI length based on a location of PDCCH control message. Forexample, a control message received in a first location or region in asubframe may be associated with a SPS configuration of a first TTI, anda control message received in a second location or region in a subframemay be associated with a SPS configuration of a second TTI. The firstand second location or region may be non-overlapping.

In another embodiment, the control command may have a new fieldindicating the length of TTI to which an SPS configuration corresponds.In some embodiments, the field may use a predetermined combination ofother fields in the control command to indicate the length of TTI towhich an SPS configuration corresponds.

In certain configurations, such as when multiple SPS configurations usea single SPS-C-RNTI, SPS reconfiguration may be avoided and/or reducedif an s-TTI length changes. In one embodiment, RRC reconfiguration maybe avoided and/or reduced in the event of an s-TTI length change (e.g.,from 2 symbol TTI to 0.5 ms TTI). For example, if a remote unit 102 isconfigured with an SPS corresponding to a 2 symbol TTI and the s-TTIlength is changed to 0.5 ms, RRC reconfiguration may be avoided and/orreduced if the SPS configuration is a function of TTI length, and onlythe TTI length changes in the SPS formula. For example, ifSPS-Interval=10 TTI has been used for the remote unit 102 whenconfigured with s-TTI=2 symbols (i.e., SPS-Interval=20 symbols), in theevent of s-TTI length change to 0.5 ms, the SPS-Interval=10 TTI, but nowequals 5 ms.

In some embodiments, a control command and/or a higher layer command(e.g., medium access control (“MAC”) control element (“CE”) (“MAC-CE”)or an RRC command) indicates to the remote unit 102 that the TTI lengthis changed. For example, an SPS activation and/or SPS reactivationcommand may be sent. In various embodiments, an SPS release controlcommand may be sent and then again an SPS activation command may be sentonce the remote unit 102 is indicated that the TTI length is changed.

In one embodiment, a network and/or a base unit 104 may inform a remoteunit 102 which control commands are for which SPS configuration whendifferent SPS configurations correspond to different TTI lengths.

In certain embodiments, a network and/or a base unit 104 may indicate afirst SPS radio network identifier (“RNI”) of a first resourceassignment via a first set of higher layer configured SPS parametersassociated with a first TTI length of a first SPS transmission set. Insuch embodiments, a higher layer may be higher than a physical layer,the first transmission set spans the first TTI length, and the first TTIlength includes a first number of symbols.

The network and/or the base unit 104, in some embodiments, may indicatea second SPS RNI of a second resource assignment via a second set ofhigher layer configured SPS parameters associated with a second TTIlength of a second SPS transmission set. In such embodiments, a higherlayer is higher than a physical layer, the second transmission set spansthe second TTI length, the second TTI length includes a second number ofsymbols, and the second number is different from the first number. Invarious embodiments, the network and/or base unit 104 may transmit thefirst resource assignment using the first SPS RNI, and transmit thesecond resource assignment using the second SPS RNI.

In one embodiment, CRC bits of each resource assignment are scrambled bya sequence initialized with the corresponding RNI. In some embodiments,the first SPS RNI and the second SPS RNI are the same. In otherembodiments, the first SPS RNI and the second SPS RNI are not the same.In various embodiments, the first and the second resource assignmentsare for UL transmissions. In certain embodiments, the first and thesecond resource assignments are for DL transmissions. In one embodiment,the network and/or the base unit 104 determines the location of the SPSresource assignment based on the TTI length. In some embodiments, thenetwork and/or the base unit 104 signals to a device a set of possibletime and/or frequency locations to be used for signaling of the SPSresource assignment for the first and second TTI lengths. For example,frequency position of the PDCCH commands may be different and the remoteunit 102 may be signaled such frequency positions.

In some embodiments, activation and/or release commands for SPSresources may use a resource assignment command for indication to theremote unit 102. The remote unit 102 may validate the activation and/orrelease command.

In certain embodiments, configuration of SPS may not enable a remoteunit 102 to start using SPS grants and/or assignments. For example, thebase unit 104 may explicitly activate SPS to enable the remote unit 102to use SPS grants and/or assignments.

In situations in which an SPS is activated by mistake, a remote unit 102may use the recurring resource for a long period of time, which mayintroduce interference to normal data transmissions. Accordingly,activation of the SPS may be performed using various methods to blockactivation of an SPS by mistake. In some embodiments, a base unit 104may explicitly release SPS without releasing an SPS RRC configuration.

In one example, a remote unit 102 may be configured with two SPSconfigurations: one with 1 ms TTI and one with 2-symbol TTI. In thisexample, none of the SPS configurations is activated for the remote unit102. If the network and/or the base unit 104 is to activate the secondSPS (i.e., the SPS with TTI=2-symbols) for the remote unit 102, thenetwork and/or the base unit 104 sends a control command to the remoteunit 102. In embodiments in which the same SPS-C-RNTI for SPSconfigurations with different TTI lengths for a remote unit 102 is used,to avoid activating the wrong SPS (i.e., the SPS with 1 ms TTI length)mistakenly, an SPS assignment validation procedure as described in FIG.6 may be used.

FIG. 6 illustrates one embodiment of TTI scheduling 600. One subframe601 has a length 602 of 1 ms. The subframe 601 includes 14 symbols thateach have a length 604 of 1/14 ms. SPS assignment validation procedurefor SPS configuration corresponding to an s-TTI length may include thatSPS activation and/or release commands may occur only during a certains-TTI index (referred to herein as “s_indx”) inside a 1 ms subframe. Forexample, the s_indx may be chosen such that SPS commands for 1 ms and 2symbol TTI length may not occur at in the same symbols: in other words,s_indx is chosen to be larger than 1 when an s-TTI inside a subframestarts with 1. Other variants may be possible (e.g., choosing s_indxsuch that it avoids with all configured SPSs with a TTI length otherthan that of the one with s_indx). In the illustrated embodiment, afirst s-indx 606 may correspond to possible locations for SPS activationand/or deactivation for a 1 ms TTI (e.g., any combination of the 3symbols of the first s-indx 606 may be used for SPS activation and/ordeactivation for the 1 ms TTI), a second s-indx 608 may correspond topossible locations for SPS activation and/or deactivation for a 2 symbolTTI (e.g., any combination of the 9 symbols of the second s-indx 608 maybe used for SPS activation and/or deactivation for the 2 symbol TTI),and a third s-indx 610 may correspond to possible locations for SPSactivation and/or deactivation for 0.5 ms TTI (e.g., any combination ofthe 2 symbols of the third s-indx 610 may be used for SPS activationand/or deactivation for the 0.5 ms TTI). In some embodiments, s_indx maybe fixed in a specification for each TTI length or may be indicated tothe remote unit 102 via higher layer signaling.

FIG. 7 illustrates another embodiment of TTI scheduling 700.Specifically, FIG. 7 illustrates one embodiment of an occasion of SPS inwhich an s-TTI occurs in a subframe not allowing s-TTI operation. Onesubframe 701 has a length 702 of 1 ms. Two other subframes 703 of length1 ms include 7 divisions that each have a length 704 of 1/7 ms.

Certain embodiments may enable reduced latency operation and may setaside some subframes (e.g., subframe 701) for legacy TTI operation(e.g., a legacy-only subframe). In such embodiments, no s-TTI operationmay be performed in those subframes. As SPS resources may occurperiodically, it is possible that an SPS for s-TTI operation maycoincides with a legacy-only subframe.

In one embodiment, a base unit 104 may send a PDCCH control command torelease the SPS momentarily, and when there is no longer suchcoincidence, the base unit 104 may send a control command to reactivatethe SPS.

In another embodiment, a base unit 104 may perform “Opportunisticmuting” of preconfigured SPS resources. For example, the base unit 104may send two different types of deactivation commands: a firstdeactivation command that is a temporary command 710 that applies toonly one subframe (i.e., deactivates SPS occasions in a single 1 mssubframe) and a second deactivation command that is a regular commandthat deactivates until the next activation and/or reactivation command.As illustrated in FIG. 7, subframes 703 may include SPS for a TTI thatis deactivated by the temporary command 710 to skip the subframe 701 andthen resume after the subframe 701. The system may operate with only asingle TTI length, e.g., legacy TTI operation or s-TTI operation or bothlegacy TTI and sTTI operation.

In certain embodiments, two types of deactivation commands may bedistinguished based on at least a field in the command set to differentvalues for the two commands. In some embodiments, the two types ofdeactivation commands may be distinguished based on a location in whichthey are sent. For example, if the command is sent in one time-frequencyregion it means the command is a first type deactivation command, and ifthe command is sent in another time-frequency region it means thecommand is a second type deactivation command.

In some embodiments, the temporary command 710 may be sent prior to thesubframe 701 in which SPS transmissions are not allowed. The timeposition (with respect to the subframe in which s-TTI operation is notallowed) of such a command may be specified in the specification. Forexample, the command may not be sent less than four s-TTIs before thestart of the legacy-only subframe 701.

FIG. 8 illustrates a further embodiment of TTI scheduling 800.Specifically, FIG. 8 illustrates another embodiment of an occasion ofSPS in which an s-TTI occurs in a subframe not allowing s-TTI operation.Each subframe has a length 802 of 1 ms. Subframes that include validscheduled SPS occurrences may include 7 divisions that each have alength 804 of 1/7 ms. Specifically, subframes 806 include validscheduled SPS occurrences 808. An SPS occurrence 810 is scheduled duringa subframe 812 that is a legacy-only subframe, in which the SPSoccurrence 810 is not allowed. Subframes 814 in the illustratedembodiment allow SPS occurrences, but do not include any scheduled SPSoccurrences.

Certain embodiments may facilitate “Rule-based SPS occasions.” Inrule-based SPS occasions, the remote unit 102 may skip the SPSoccurrence 810 in the legacy-only subframe 812. The next SPS occasionmay by determined by an SPS formula and/or bit-map in a specification.For example, as illustrated, the next SPS occasion may be the normallyscheduled SPS occurrence 808 that follows the skipped SPS occurrence810.

FIG. 9 illustrates yet another embodiment of TTI scheduling 900.Specifically, FIG. 9 illustrates yet another embodiment of an occasionof SPS in which an s-TTI occurs in a subframe not allowing s-TTIoperation. Each subframe has a length 902 of 1 ms. Subframes thatinclude valid scheduled SPS occurrences may include 7 divisions thateach have a length 904 of 1/7 ms. Specifically, subframes 906 includevalid scheduled SPS occurrences 908. An SPS occurrence 910 is scheduledduring a subframe 912 that is a legacy-only subframe, in which the SPSoccurrence 910 is not allowed. Subframes 914 in the illustratedembodiment allow SPS occurrences, but do not include any scheduled SPSoccurrences.

In various embodiments, an occasion which does not belong to the SPSoccasion set (i.e., SPS formula and/or bit-map), may be used as areplacement SPS occasion for an SPS occasion that interferes with alegacy-only subframe. Such a replacement SPS occasion may be adeterministic function of the SPS configuration and the skipped SPSoccasion. For example, the replacement SPS occasion may be a first s-TTIlocation outside of the legacy-only subframe. As another example, thereplacement SPS occasion may use the same s-TTI index as the skippeds-TTI in the next subframe that allows both legacy and s-TTI operation(e.g., replacement SPS occurrence 916 that is used because SPSoccurrence 910 is skipped).

In certain embodiments, to reduce control overhead and also remote unit102 processing for PDCCH, the SPS-C-RNTI for reduced latency operationmay be only processed at certain s-TTIs (e.g., first occasion in asubframe coinciding with 1 ms TTI PDCCH control region in the timedomain).

In one embodiment, when an SPS resource (occasion) of a s-TTI for adevice occurs at a subframe where s-TTI operation is not allowed (SPSresources are periodic and hence such occurrences are possible), thenetwork and/or the base unit 104 may inform the device to not use thatSPS resource and/or occasion.

In some embodiments, a method may include indicating a first indicationto a device, the first indication corresponding to a SPS resourceassignment determining a first set of resources to be used for a firstset of transmissions using a first TTI. The method, in variousembodiments, may include indicating a second indication to the device,the second indication corresponding to a second set of resources for asecond transmission using a second TTI. In such embodiments, a subset ofthe transmissions of the first set may overlap with the secondtransmission in time. The method, in one embodiment, may includeindicating a third indication to the device, to not use (e.g., ignore,drop) the subset of the transmissions of the first set.

In one embodiment, the first set of transmissions are for s-TTI and/orreduced latency, and the second transmission using the second TTI is aregular 1 ms subframe transmission. In certain embodiments, the subsetof the transmissions of the first set corresponds to transmissionsbelonging to a single subframe. In one embodiment, the third indicationis a physical layer indication. In various embodiments, the first set oftransmissions and the second transmission are UL transmissions, and thethird indication is a higher layer indication. In various embodiments,the first set of transmissions and the second transmission are ULtransmissions and the third indication is an implicit indication thatdrops the subset of the transmissions of the first set. In oneembodiment, the first TTI length is 1 ms.

In some embodiments, there may be legacy SPS collisions with s-TTI. Incertain LTE systems, dynamic scheduling of best effort data may occur ontop of SPS, but the SPS allocations may take precedence over schedulingconflicts.

However, if a remote unit 102 is configured with a SPS corresponding to1 ms TTI in UL, and a dynamic grant for an s-TTI with colliding timeand/or time-frequency resources with the SPS resources is received bythe remote unit 102, the remote unit 102 may prioritize the low-latencydata transmission if it is configured via higher layers to drop the 1 msSPS transmission; otherwise, the 1 ms SPS transmission may beprioritized. In one embodiment, in case of resource conflicts, thepriority rule may be fixed in the specification, for example, SPSprioritized over dynamic scheduling; s-TTI operation prioritized overlegacy TTI operation for given scheduling type (dynamic or SPS); SPSusing legacy TTI prioritized over dynamic scheduling using s-TTI; and/orSPS using s-TTI prioritized over dynamic scheduling using legacy TTI.

In one embodiment, a device, such as in UL, may prioritize onetransmission over the second transmission (one of the transmissions is atransmission corresponding to SPS operation).

In certain embodiments, one method at the device may includetransmitting a first transmission in UL using a first TTI in a firstresource, and dropping (e.g., not transmitting) a second UL transmissionusing a second TTI corresponding to a second SPS resource for a thirdperiod in time. In such embodiments, the first and the second resourcemay overlap in time in the third period. In various embodiments, thedevice may be configured via higher layers to drop the second ULtransmission.

In some embodiments, SPS may have a non-periodic pattern. For example,SPS occasions may follow a pattern that is non-periodic (e.g., a bit-mappattern) which is indicated to the device, such as by higher layersignaling (e.g., RRC signaling). In one embodiment, an SPS pattern maybe a bit-map pattern indicated by higher layer signaling. In someembodiments, SPS occasions are indicated by a bit-map to a device viahigher layer signaling. In another embodiment, an indication may includea first periodicity for a first time duration, and a second periodicityfor a second duration, e.g., after the end of the first time duration.The first periodicity may be smaller than the second periodicity.

FIG. 10 is a schematic flow chart diagram illustrating one embodiment ofa method 1000 for scheduling of TTIs. In some embodiments, the method1000 is performed by an apparatus, such as the base unit 104. In certainembodiments, the method 1000 may be performed by a processor executingprogram code, for example, a microcontroller, a microprocessor, a CPU, aGPU, an auxiliary processing unit, a FPGA, or the like.

The method 1000 may include determining 1002 a first SPS RNI for a firstresource assignment associated with a first TTI including a first numberof symbols. The method 1000 may also include determining 1004 a secondSPS RNI for a second resource assignment associated with a second TTIincluding a second number of symbols different from the first number ofsymbols. The method 1000 may include transmitting 1006 informationindicating the first resource assignment using the first SPS RNI. Themethod 1000 may include transmitting 1008 information indicating thesecond resource assignment using the second SPS RNI.

FIG. 11 is a schematic flow chart diagram illustrating one embodiment ofa method 1100 for scheduling of TTIs. In some embodiments, the method1100 is performed by an apparatus, such as the remote unit 102. Incertain embodiments, the method 1100 may be performed by a processorexecuting program code, for example, a microcontroller, amicroprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, orthe like.

The method 1100 may include receiving 1102 information indicating afirst resource assignment associated with a first TTI including a firstnumber of symbols. The method 1100 may also include receiving 1104information indicating a second resource assignment associated with asecond TTI including a second number of symbols different from the firstnumber of symbols. The method 1100 may include determining 1106 thefirst resource assignment using a first SPS RNI. The method 1100 mayalso include determining 1108 the second resource assignment using asecond SPS RNI.

Embodiments may be practiced in other specific forms. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. An apparatus comprising: a processor that:determines a first semi-persistent scheduling resource assignmentindicating a first set of resources, the first set of resourcescomprising a first plurality of time domain resources, and the firstsemi-persistent scheduling resource assignment is associated with afirst semi-persistent scheduling configuration, wherein each time domainresource of the first plurality of time domain resources has a firsttransmission time interval length corresponds to a first number ofsymbols; and determines a second semi-persistent scheduling resourceassignment indicating a second set of resources, the second set ofresources comprising a second plurality of time domain resources, andthe second semi-persistent scheduling resource assignment is associatedwith a second semi-persistent scheduling configuration, wherein eachtime domain resource of the second plurality of time domain resourceshas a second transmission time interval length corresponds to a secondnumber of symbols, and wherein the first transmission time intervallength is different from the second transmission time interval length;and a transmitter that: transmits the first semi-persistent schedulingresource assignment on a first time and frequency resource using a firstsemi-persistent scheduling radio network identifier to a user equipment;and transmits the second semi-persistent scheduling resource assignmenton a second time and frequency resource using a second semi-persistentscheduling radio network identifier to the user equipment, wherein thefirst semi-persistent scheduling configuration and the secondsemi-persistent scheduling configuration are configured at the sametime, the first semi-persistent scheduling resource assignment isconfigured to be identified as a result of the first semi-persistentscheduling resource assignment being transmitted on the first time andfrequency resource, the second semi-persistent scheduling resourceassignment is configured to be identified as a result of the secondsemi-persistent scheduling resource assignment being transmitted on thesecond time and frequency resource, and the first time and frequencyresource is different from the second time and frequency resource.
 2. Amethod comprising: determining a first semi-persistent schedulingresource assignment indicating a first set of resources, the first setof resources comprising a first plurality of time domain resources, andthe first semi-persistent scheduling resource assignment is associatedwith a first semi-persistent scheduling configuration, wherein each timedomain resource of the first plurality of time domain resources has afirst transmission time interval length corresponds to a first number ofsymbols; determining a second semi-persistent scheduling resourceassignment indicating a second set of resources, the second set ofresources comprising a second plurality of time domain resources, andthe second semi-persistent scheduling resource assignment is associatedwith a second semi-persistent scheduling configuration, wherein eachtime domain resource of the second plurality of time domain resourceshas a second transmission time interval length corresponds to a secondnumber of symbols, and wherein the first transmission time intervallength is different from the second transmission time interval length;transmitting, by a transmitter, the first semi-persistent schedulingresource assignment on a first time and frequency resource using a firstsemi-persistent scheduling radio network identifier to a user equipment;and transmitting, by the transmitter, the second semi-persistentscheduling resource assignment on a second time and frequency resourceusing a second semi-persistent scheduling radio network identifier tothe user equipment, wherein the first semi-persistent schedulingconfiguration and the second semi-persistent scheduling configurationare configured at the same time, the first semi-persistent schedulingresource assignment is configured to be identified as a result of thefirst semi-persistent scheduling resource assignment being transmittedon the first time and frequency resource, the second semi-persistentscheduling resource assignment is configured to be identified as aresult of the second semi-persistent scheduling resource assignmentbeing transmitted on the second time and frequency resource, and thefirst time and frequency resource is different from the second time andfrequency resource.
 3. The method of claim 2, wherein the firstsemi-persistent scheduling radio network identifier and the secondsemi-persistent scheduling radio network identifier are the same.
 4. Themethod of claim 2, wherein the first semi-persistent scheduling radionetwork identifier and the second semi-persistent scheduling radionetwork identifier are different.
 5. The method of claim 2, wherein thefirst and second semi-persistent scheduling resource assignments are foruplink transmissions.
 6. The method of claim 2, wherein the first andsecond semi-persistent scheduling resource assignments are for downlinktransmissions.
 7. The method of claim 2, further comprising determininga location of the first semi-persistent scheduling resource assignmentbased on the first number of symbols and determining a location of thesecond semi-persistent scheduling resource assignment based on thesecond number of symbols.
 8. The method of claim 2, further comprisingtransmitting information indicating a location in a subframe for one ormore of semi-persistent scheduling activation and semi-persistentscheduling deactivation commands.
 9. The method of claim 2, furthercomprising transmitting information indicating one or more ofsemi-persistent scheduling activation and semi-persistent schedulingdeactivation commands in a predetermined location in a subframe.
 10. Anapparatus comprising: a receiver that: receives, from a transmittingdevice, a first semi-persistent scheduling resource assignment on afirst time and frequency resource, wherein the first semi-persistentscheduling resource assignment indicates a first set of resources, thefirst set of resources comprises a first plurality of time domainresources, the first semi-persistent scheduling resource assignment isassociated with a first semi-persistent scheduling configuration, andeach time domain resource of the first plurality of time domainresources has a first transmission time interval length corresponds to afirst number of symbols; and receives, from the transmitting device, asecond semi-persistent scheduling resource assignment on a second timeand frequency resource, wherein the second semi-persistent schedulingresource assignment indicates a second set of resources, the second setof resources comprises a second plurality of time domain resources, thesecond semi-persistent scheduling resource assignment is associated witha second semi-persistent scheduling configuration, each time domainresource of the second plurality of time domain resources has a secondtransmission time interval length corresponds to a second number ofsymbols, the first transmission time interval length is different fromthe second transmission time interval length, and the first time andfrequency resource is different from the second time and frequencyresource; and a processor that: identifies the first semi-persistentscheduling resource assignment as a result of the first semi-persistentscheduling resource assignment being transmitted on the first time andfrequency resource; identifies the second semi-persistent schedulingresource assignment as a result of the second semi-persistent schedulingresource assignment being transmitted on the second time and frequencyresource; determines the first semi-persistent scheduling resourceassignment using a first semi-persistent scheduling radio networkidentifier; and determines the second semi-persistent schedulingresource assignment using a second semi-persistent scheduling radionetwork identifier; wherein the apparatus is configured with the firstsemi-persistent scheduling configuration and the second semi-persistentscheduling configuration at the same time.
 11. A method comprising:receiving, at a user equipment from a transmitting device, a firstsemi-persistent scheduling resource assignment on a first time andfrequency resource, wherein the first semi-persistent schedulingresource assignment indicates a first set of resources, the first set ofresources comprises a first plurality of time domain resources, thefirst semi-persistent scheduling resource assignment is associated witha first semi-persistent scheduling configuration, and each time domainresource of the first plurality of time domain resources has a firsttransmission time interval length corresponds to a first number ofsymbols; receiving, at the user equipment from the transmitting device,a second semi-persistent scheduling resource assignment on a second timeand frequency resource, wherein the second semi-persistent schedulingresource assignment indicates a second set of resources, the second setof resources comprises a second plurality of time domain resources, thesecond semi-persistent scheduling resource assignment is associated witha second semi-persistent scheduling configuration, each time domainresource of the second plurality of time domain resources has a secondtransmission time interval length corresponds to a second number ofsymbols, the first transmission time interval length is different fromthe second transmission time interval length and the first time andfrequency resource is different from the second time and frequencyresource; identifying the first semi-persistent scheduling resourceassignment as a result of the first semi-persistent scheduling resourceassignment being transmitted on the first time and frequency resource;identifying the second semi-persistent scheduling resource assignment asa result of the second semi-persistent scheduling resource assignmentbeing transmitted on the second time and frequency resource; determiningthe first semi-persistent scheduling resource assignment using a firstsemi-persistent scheduling radio network identifier; and determining thesecond semi-persistent scheduling resource assignment using a secondsemi-persistent scheduling radio network identifier, wherein the userequipment is configured with the first semi-persistent schedulingconfiguration and the second semi-persistent scheduling configuration atthe same time.
 12. The method of claim 11, wherein the firstsemi-persistent scheduling resource assignment is for uplinktransmissions, and the method further comprises: receiving adeactivation command; determining at least one time domain resource ofthe first plurality of time domain resources; and in response toreceiving the deactivation command, deactivating semi-persistentscheduling related data transmission on the at least one time domainresource of the first plurality of time domain resources.
 13. The methodof claim 12, wherein the deactivation command is a first deactivationcommand, and the method further comprises: receiving a seconddeactivation command; and in response to receiving the seconddeactivation command, deactivating semi-persistent scheduling relateddata transmission until reception of a semi-persistent schedulingactivation command or a semi-persistent scheduling reactivation command.14. The method of claim 11, wherein the first transmission time intervallength corresponds to a first number of symbols, and the secondtransmission time interval length corresponds to a second number ofsymbols.
 15. A method comprising: receiving, at a user equipment from atransmitting device, a first semi-persistent scheduling resourceassignment on a first time and frequency scheduling resource and asecond semi-persistent scheduling resource assignment on a second timeand frequency scheduling resource, wherein the first semi-persistentscheduling resource assignment indicates a first set of periodic timedomain resources, each resource of the first set of periodic time domainresources has a first transmission time interval length corresponds to afirst number of symbols, and the first time and frequency schedulingresource is different from the second time and frequency schedulingresource; identifying the first semi-persistent scheduling resourceassignment as a result of the first semi-persistent scheduling resourceassignment being transmitted on the first time and frequency schedulingresource determining, at the user equipment, a first resource of thefirst set of periodic time domain resources that overlaps with aresource used for transmissions based on a second transmission timeinterval length corresponds to a second number of symbols; determining,at the user equipment, a second resource of the first transmission timeinterval length that does not overlap with the resource used fortransmissions based on the second transmission time interval length; andusing the second resource for semi-persistent scheduling related datatransmissions and not using the first resource of the first set ofperiodic time domain resources for semi-persistent scheduling relateddata transmissions, wherein the first transmission time interval lengthand the second transmission time interval length are different.
 16. Themethod of claim 15, further comprising receiving a message indicatingthe resources used for transmissions based on the second transmissiontime interval length.
 17. The method of claim 15, wherein the firsttransmission time interval length corresponds to a shortenedtransmission time interval length, and the second transmission timeinterval length corresponds to a legacy transmission time intervallength, and wherein the shortened transmission time interval length issmaller than the legacy transmission time interval length.
 18. Themethod of claim 15, further comprising determining the second resourcefrom the first set of periodic time domain resources.
 19. The method ofclaim 15, further comprising determining the second resource from athird set of time domain resources not overlapping with the first set ofperiodic time domain resources.
 20. The method of claim 15, furthercomprising determining the second resource based on time domaininformation of the first resource of the first set of periodic timedomain resources and the time domain information of the resource usedfor transmissions based on the second transmission time interval length.21. The method of claim 15, wherein the first semi-persistent schedulingresource assignment comprises a bit-map pattern.
 22. The method of claim15, wherein a periodicity of the first set of time domain resources isdefined based on a number of transmission time intervals.
 23. The methodof claim 22, further comprising: receiving an indication that indicatesa third transmission time interval length for the first semi-persistentscheduling resource assignment; and determining the periodicity of thefirst time domain resources based on the third transmission timeinterval length, wherein the first transmission time interval length andthe third transmission time interval length are different.
 24. Themethod of claim 2, wherein the user equipment being configured with thefirst semi-persistent scheduling configuration and the secondsemi-persistent scheduling configuration at the same time comprisesenabling the user equipment to receive the first semi-persistentscheduling resource assignment or the second semi-persistent schedulingresource assignment based on the first semi-persistent schedulingconfiguration and the second semi-persistent scheduling configuration.25. The method of claim 2, wherein the first semi-persistent schedulingconfiguration and the second semi-persistent scheduling configurationare capable of being activated by the user equipment.